didac wrote on Jun 4th, 2008, 2:57am:But recently I've seen efforts of integration of power detectors on-chip, they assume a high input impedance to avoid loading and are based in rms voltage so I think that they are measuring "apparent" power, is it right?
I don't understand a meaning of "apparent" power.
Do you mean reactive power ?
Assume a situation where output of DUT is connected to
didac wrote on Jun 4th, 2008, 2:57am:But recently I've seen efforts of integration of power detectors on-chip, they assume a high input impedance to avoid loading and are based in rms voltage so I think that they are measuring "apparent" power, is it right?
I don't understand a mean of "apparent" power.
Do you mean reactive power ?
Assume a situation where output of DUT is connected to load impedance(=z) by very short line(volatge is uniform over line length).
You can calculate true power delivered to load by knowing voltage of line and load impedance(=z). Here voltage is measured by infinite input impedance probe.
This is a same method as a definition of dbm() function in Agilent ADS.
Syntax : y = dbm(voltage, z)
Examples :
y = dbm(100) returns 50
y = dbm(8-6*j) returns 30
Here z is omitted and it is assumed as 50Ohm.